# RTC_SetDateTimeAsync

## C Specification

  `#include <nitro/rtc.h>`

      RTCResult RTC_SetDateTimeAsync(
                  const RTCDate* date,
                  const RTCTime* time,
                  RTCCallback callback,
                  void*       arg );

## Description

This function asynchronously writes date and time data to the real time clock. It sends date and time data to ARM7 and returns the process result without waiting for a response from the processor.

If this function fails, no operation is performed and no user callback function is called.

## Cautions

Do not define parameter values of nonexistent dates or times. However, you may specify a day of the week that does not match the actual calendar.

Values are written to the variables specified by the `date` and `time` arguments asynchronously with respect to the function. Do not use these variables for anything else until a user callback function confirms the completion of this asynchronous operation.

## Arguments

`date` | Pointer to `RTCDate` containing date information to set.
`time` | Pointer to `RTCTime` containing time information to set.
`callback` | Pointer to specific `RTCCallback` function to be used.
`arg` | User context.

## Return Values

If the request succeeds, it returns 0.
If the request fails, it returns some numeric value other than 0.

## See Also

`RTC_SetDateTime, RTC_GetDateTime, RTC_GetDateTimeAsync, RTCResult, RTCDate, RTCTime, RTCCallback`

## Revision History

05/18/2004 Initial Version